In general, a straw is used for drinking beverage such as juice or milk, and is packaged with a cover (vinyl cover) for the sake of hygiene.
When packaging straws, two strip-shaped films are automatically and continuously supplied while straws are consecutively placed to be spaced apart from each other between the two films. Then, the overlapped films between the adjacent straws are welded to package the straws.
The straw sheet (package) is inspected for defects of the straw sheet prior to shipment.
Conventionally, since inspection of the straw sheet for defects (foreign material, damage, etc.) is performed manually, the inspection work is very troublesome and inconvenient. In particular, it is difficult to accurately check fine foreign material included in the straw sheet, the size of the straw sheet and sealing defects of the straw sheet through the manual work. Further, inspection errors may occur depending on the skill of an inspector, and thus reliability of the inspection may be decreased.
Therefore, there is needed a measure for accurately and quickly inspecting defects of a straw sheet packaging straws.